Draw a labelled diagram to make a soft iron bar as an electromagnet. Describe in steps the procedure.

1. Take a soft iron bar PQ and wind a thin insulated copper wire around the bar.
2. Connect a cell or a battery and a key K in series between the ends of a coil as shown in the below figure.
3. When key is closed current passes through the winding of the coil and the bar becomes a magnet.
4. But when key is opened the current stops flowing in the coil and bar gets demagnetized.

So, soft iron bar behaves as an electromagnet when current passes through the coil.